Bought some great lights for use with the a-bike:
Electron Backupz seatpost 6 LED Light (£10)
Electron Backupz front 5 LED light (£13)
They attach to the seatpost/handlebars using an elastic cord and do not hinder folding in any way.
You can get cheaper electron backupz with less LEDs, but these seem to be the best at the moment.
Neil.